# US 2021/0340943 A1 · Fuel injection valve

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2021/0340943 A1
- Document ID: US20210340943A1
- Status: Published application
- Kind: A1
- Application number: 17/376,489
- Filed: 2021-07-15
- Published: 2021-11-04
- Earliest claimed: 2019-01-17
- Assignees: Denso Corporation
- Applicants: Denso Corporation
- Inventors: Hideo TSUKADA; Kouichi MOCHIZUKI
- Web page: https://patentgrep.com/patent/US20210340943A1

## CPC

- F02M 51/061: {using electromagnetic operating means}
- F02M 51/0614: {characterised by arrangement of electromagnets or fixed armature}
- F02M 2200/08: Fuel-injection apparatus having special means for influencing magnetic flux, e.g. for shielding or guiding magnetic flux
- F02M 2200/8061: involving press-fit, i.e. interference or friction fit
- F02M 2200/90: Selection of particular materials
- F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF

## Abstract

A movable core is driven by a magnetic attraction force with a fixed core to move a valve body to inject fuel. A yoke accommodates the fixed core. A coil is in a coil chamber between the fixed core and the yoke. The coil chamber is filled with a filling resin member being electrically insulative. The fixed core has a core facing surface facing the movable core and includes a protruding portion that protrudes radially outer side and is in contact with the yoke to conduct the magnetic flux. A resin molding flow channel is formed in the protruding portion to cause molten resin serving as the filling resin member to flow into the coil chamber. A length of the protruding portion along a cylinder center line is set to be shorter toward a radially outer side.

## Claims

### Claim 1

A fuel injection valve comprising:
a fixed core configured to form a part of a magnetic circuit that is to cause a magnetic flux to flow therethrough;
a movable core configured to form a part of the magnetic circuit and configured to be driven by a magnetic attraction force generated in a gap between the movable core and the fixed core;
a valve body configured to perform a valve opening operation caused by driving the movable core to open a nozzle hole to inject fuel;
a yoke configured to form a part of the magnetic circuit and accommodating the fixed core;
a coil placed in a coil chamber between the fixed core and the yoke and configured to generate the magnetic flux on energization; and
a filling resin member with which the coil chamber is filled and having an electrical insulation property, wherein
the fixed core includes:
a cylindrical main body portion that has a core facing surface facing the movable core; and
a protruding portion that protrudes radially outward from an outer peripheral surface of the cylindrical main body portion and is in contact with the yoke to cause the magnetic flux to pass therethrough,
the protruding portion defines a resin molding flow channel to cause molten resin serving as the filling resin member to flow into the coil chamber, and
a length of the protruding portion in a direction of a cylinder center line of the fixed core is set to be shorter toward a radially outer side of the fixed core.

### Claim 2 (depends on 1)

The fuel injection valve according to claim 1, wherein
the protruding portion is press-fitted to the yoke in a direction of the driving.

### Claim 3 (depends on 1)

The fuel injection valve according to claim 1, wherein
the length of the protruding portion in the direction of the cylinder center line gradually decreases from a radially inner side to the radially outer side of the fixed core.

### Claim 4 (depends on 1)

The fuel injection valve according to claim 1, wherein
the resin molding flow channel is formed between a notch portion, which is in a protruding end surface of the protruding portion, and the yoke.

### Claim 5 (depends on 1)

The fuel injection valve according to claim 1, wherein
a magnetic path cross-sectional area of the magnetic circuit at a contact portion between the protruding portion and the yoke is larger than a magnetic path cross-sectional area of the magnetic circuit in the core facing surface.

### Claim 6 (depends on 1)

The fuel injection valve according to claim 1, wherein
the resin molding flow channel includes a plurality of the resin molding flow channels placed at equal intervals around the cylinder center line of the cylindrical main body portion.